LibGuides: Critical Skepticism: Exercises

Chocolate

Chocolate is delicious, but media reports encourage us that is is also delicious. Evaluate the evidence and consider if you should add chocolate to your diet. What are the strengths and limitations t the arguments?

Dark chocolate is now a health food. Here’s how that happened.
So how in the world could a chocolate bar be convincingly sold as a health food? You can thank a decades-long effort by the chocolate industry.

Over the past 30 years, food companies like Nestlé, Mars, Barry Callebaut, and Hershey’s — among the world’s biggest producers of chocolate — have poured millions of dollars into scientific studies and research grants that support cocoa science. (from the article)
Should You Eat Chocolate Every Day?
While there haven’t been all that many scientific studies done on the health benefits of cocoa, those that have been published have all come to the same conclusion: The phytochemicals (plant chemicals) in cocoa known as flavanols are good for your health and, in particular, your heart. (From the article)
Enhancing Human Cognition with Cocoa Flavonoids
Enhancing cognitive abilities has become a fascinating scientific challenge, recently driven by the interest in preventing age-related cognitive decline and sustaining normal cognitive performance in response to cognitively demanding environments. In recent years, cocoa and cocoa-derived products, as a rich source of flavonoids, mainly the flavanols sub-class, have been clearly shown to exert cardiovascular benefits.

Cocoa Flavanols Lower Blood Pressure And Increase Blood Vessel Function In Healthy People
Cardiovascular disease (CVD) represents the most common cause of death worldwide. The consumption of natural polyphenol-rich foods, and cocoa in particular, has been related to a reduced risk of CVD, including coronary heart disease and stroke. Intervention studies strongly suggest that cocoa exerts a beneficial impact on cardiovascular health, through the reduction of blood pressure (BP), improvement of vascular function, modulation of lipid and glucose metabolism, and reduction of platelet aggregation. These potentially beneficial effects have been shown in healthy subjects as well as in patients with risk factors (arterial hypertension, diabetes, and smoking) or established CVD (coronary heart disease or heart failure). Several potential mechanisms are supposed to be responsible for the positive effect of cocoa; among them activation of nitric oxide (NO) synthase, increased bioavailability of NO as well as antioxidant, and anti-inflammatory properties. It is the aim of this review to summarize the findings of cocoa and chocolate on BP and vascular function. (From the abstract)

Bees

Bees are dying, but there is disagreement as to the cause. If you were in a position to make a choice about Niconicotinoid pesiticides what would you consider about the evidence? See the items below.

Beyond Pesticides
Beyond Pesticides (formerly National Coalition Against the Misuse of Pesticides) is a 501(c)3 nonprofit organization headquartered in Washington, D.C., which works with allies in protecting public health and the environment to lead the transition to a world free of toxic pesticides. The founders, who established Beyond Pesticides as a nonprofit membership organization in 1981, felt that without the existence of such an organized, national network, local, state and national pesticide policy would become, under chemical industry pressure, increasingly unresponsive to public health and environmental concerns.
Beyond Pesticides believes that people must have a voice in decisions that affect them directly. We believe decisions should not be made for us by chemical companies or by decision makers who either do not have all of the facts or refuse to consider them.(from about us)
EU to completely ban outdoor use of pesticides
Citing concerns for food production, the environment and biodiversity, the European Union is set to "completely ban" the outdoor use of neonicotinoid insecticides that have been blamed for killing bees, and for keeping other bees from laying eggs.
"All outdoor use of the three substances will be banned and the neonicotinoids in question will only be allowed in permanent greenhouses where no contact with bees is expected," the EU announced on Friday.(from the transcript)
Pesticides are harming bees
https://www.npr.org/sections/thesalt/2017/06/29/534852611/pesticides-are-harming-bees-but-not-everywhere-major-new-study-shows

Chronic exposure to neonicotinoids reduces honey bee health near corn crops
Experiments linking neonicotinoids and declining bee health have been criticized for
not simulating realistic exposure. Here we quantified the duration and magnitude
of neonicotinoid exposure in Canada’s corn-growing regions and used these data
to design realistic experiments to investigate the effect of such insecticides on
honey bees. Colonies near corn were naturally exposed to neonicotinoids for up to
4 months—the majority of the honey bee’s active season. Realistic experiments
showed that neonicotinoids increased worker mortality and were associated with
declines in social immunity and increased queenlessness over time. We also
discovered that the acute toxicity of neonicotinoids to honey bees doubles in
the presence of a commonly encountered fungicide. Our work demonstrates that
field-realistic exposure to neonicotinoids can reduce honey bee health in
corn-growing regions.
Country-specific effects of neonicotinoid pesticides on honey bees and wild bees
Early studies of the impacts of neonicotinoid insecticides on insect pollinators indicated considerable harm. However, lingering criticism was that the studies did not represent field-realistic levels of the chemicals or prevailing environmental conditions. Two studies, conducted on different crops and on two continents, now substantiate that neonicotinoids diminish bee health (see the Perspective by Kerr). Tsvetkov et al. find that bees near corn crops are exposed to neonicotinoids for 3 to 4 months via nontarget pollen, resulting in decreased survival and immune responses, especially when coexposed to a commonly used agrochemical fungicide. Woodcock et al., in a multicounty experiment on rapeseed in Europe, find that neonicotinoid exposure from several nontarget sources reduces overwintering success and colony reproduction in both honeybees and wild bees. These field results confirm that neonicotinoids negatively affect pollinator health under realistic agricultural conditions.

Science Triumphs at the EPA
In The Neonic Ban: A Scientific Fraud Becomes Enshrined In EU Regulatory Law, I described the many elements of corruption that led to Europe’s recently announced ban on neonic insecticides (“neonics”) which is based on the fallacy that they are responsible for a supposed collapse in bee populations. In fact, bee populations are rising on every habitable continent in the world, and have been since neonics first came on the market.(from the blog)